Question

A 0.80-kg block is held in place against the spring by a
67-Nhorizontal external force. The external force is removed, and
theblock is projected with a velocity v1 = 1.2
m/supon separation from the spring. The block descends a ramp and
hasa velocity v2 = 1.9 m/s at the bottom.
Thetrack is frictionless between points A and B.
Theblock enters a rough section at B, extending
toE. The coefficient of kinetic friction is 0.39.
Thevelocity of the block is v3 = 1.4 m/s
atC. The block moves on to D, where it stops.
InFig. 7.4, the force constant of the spring is closest to: